1. Noun
One of the very small invisible particles of which all matter is supposed to consist.
2. Noun
The smallest part of any substance which possesses the characteristic properties and qualities of that substance, and which can exist alone in a free state.
3. Noun
A group of atoms so united and combined by chemical affinity that they form a complete, integrated whole, being the smallest portion of any particular compound that can exist in a free state; as, a molecule of water consists of two atoms of hydrogen and one of oxygen. Cf. Atom.
4. Noun
Two or more atoms joined together.
A group of two or more atoms bonded together as a discrete unit.
“A water molecule contains two hydrogen atoms and one oxygen atom.”
5. Noun
(physics and chemistry) the simplest structural unit of an element or compound
Vocabulary classified under Chemistry
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